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authorLinus Torvalds <torvalds@linux-foundation.org>2014-08-08 11:14:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-08-08 11:14:29 -0700
commitb3345d7c57d70e6cb6749af25cdbe80515582e99 (patch)
tree04cce706bc7e944ad1fb257108a8ae735948f97f /arch/arm/lib
parent44c916d58b9ef1f2c4aec2def57fa8289c716a60 (diff)
parentc2fff85e21818952aa0ee5778926beee6c03e579 (diff)
Merge tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC platform changes from Olof Johansson: "This is the bulk of new SoC enablement and other platform changes for 3.17: - Samsung S5PV210 has been converted to DT and multiplatform - Clock drivers and bindings for some of the lower-end i.MX 1/2 platforms - Kirkwood, one of the popular Marvell platforms, is folded into the mvebu platform code, removing mach-kirkwood - Hwmod data for TI AM43xx and DRA7 platforms - More additions of Renesas shmobile platform support - Removal of plat-samsung contents that can be removed with S5PV210 being multiplatform/DT-enabled and the other two old platforms being removed New platforms (most with only basic support right now): - Hisilicon X5HD2 settop box chipset is introduced - Mediatek MT6589 (mobile chipset) is introduced - Broadcom BCM7xxx settop box chipset is introduced + as usual a lot other pieces all over the platform code" * tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits) ARM: hisi: remove smp from machine descriptor power: reset: move hisilicon reboot code ARM: dts: Add hix5hd2-dkb dts file. ARM: debug: Rename Hi3716 to HIX5HD2 ARM: hisi: enable hix5hd2 SoC ARM: hisi: add ARCH_HISI MAINTAINERS: add entry for Broadcom ARM STB architecture ARM: brcmstb: select GISB arbiter and interrupt drivers ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs ARM: configs: enable SMP in bcm_defconfig ARM: add SMP support for Broadcom mobile SoCs Documentation: arm: misc updates to Marvell EBU SoC status Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC ARM: mvebu: fix build without platforms selected ARM: mvebu: add cpuidle support for Armada 38x ARM: mvebu: add cpuidle support for Armada 370 cpuidle: mvebu: add Armada 38x support cpuidle: mvebu: add Armada 370 support cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7 ARM: mvebu: export the SCU address ...
Diffstat (limited to 'arch/arm/lib')
-rw-r--r--arch/arm/lib/delay.c26
1 files changed, 22 insertions, 4 deletions
diff --git a/arch/arm/lib/delay.c b/arch/arm/lib/delay.c
index 5306de350133..312d43eb686a 100644
--- a/arch/arm/lib/delay.c
+++ b/arch/arm/lib/delay.c
@@ -19,6 +19,7 @@
* Author: Will Deacon <will.deacon@arm.com>
*/
+#include <linux/clocksource.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/kernel.h>
@@ -36,6 +37,7 @@ struct arm_delay_ops arm_delay_ops = {
static const struct delay_timer *delay_timer;
static bool delay_calibrated;
+static u64 delay_res;
int read_current_timer(unsigned long *timer_val)
{
@@ -47,6 +49,11 @@ int read_current_timer(unsigned long *timer_val)
}
EXPORT_SYMBOL_GPL(read_current_timer);
+static inline u64 cyc_to_ns(u64 cyc, u32 mult, u32 shift)
+{
+ return (cyc * mult) >> shift;
+}
+
static void __timer_delay(unsigned long cycles)
{
cycles_t start = get_cycles();
@@ -69,18 +76,24 @@ static void __timer_udelay(unsigned long usecs)
void __init register_current_timer_delay(const struct delay_timer *timer)
{
- if (!delay_calibrated) {
- pr_info("Switching to timer-based delay loop\n");
+ u32 new_mult, new_shift;
+ u64 res;
+
+ clocks_calc_mult_shift(&new_mult, &new_shift, timer->freq,
+ NSEC_PER_SEC, 3600);
+ res = cyc_to_ns(1ULL, new_mult, new_shift);
+
+ if (!delay_calibrated && (!delay_res || (res < delay_res))) {
+ pr_info("Switching to timer-based delay loop, resolution %lluns\n", res);
delay_timer = timer;
lpj_fine = timer->freq / HZ;
+ delay_res = res;
/* cpufreq may scale loops_per_jiffy, so keep a private copy */
arm_delay_ops.ticks_per_jiffy = lpj_fine;
arm_delay_ops.delay = __timer_delay;
arm_delay_ops.const_udelay = __timer_const_udelay;
arm_delay_ops.udelay = __timer_udelay;
-
- delay_calibrated = true;
} else {
pr_info("Ignoring duplicate/late registration of read_current_timer delay\n");
}
@@ -91,3 +104,8 @@ unsigned long calibrate_delay_is_known(void)
delay_calibrated = true;
return lpj_fine;
}
+
+void calibration_delay_done(void)
+{
+ delay_calibrated = true;
+}